X1 not starting up

You could try closing X1 with the Shift+Close trick. This is supposed to force X1 to write its configuration before closing.

Or maybe even just completely close X1 before you shut down your PC. This ensures that the files are written before Windows completes its own shutdown.

In earlier versions of X1, I knew where it wrote the screen position data so I could go and delete it. I'm afraid I can't see where they keep that data now. They probably moved it into an xml file rather than the original ini file.

Perhaps it is in the file UIConfig.xml.

Among other screen data, it holds stuff like:

<MainWindowW>1410</MainWindowW>
<MainWindowH>964</MainWindowH>

In your shoes I would try the first ideas. If they fail, then close X1 and rename the file UIConfig.xml to something like UIConfig.xml.old. Then X1 will recreate that file when it next starts. If that fails then you can recover that file.

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